This invention relates to a tillage attachment for mounting on agricultural implement of the type comprising a tool bar, ground wheels for supporting the tool bar for movement across the ground and means for causing the tool bar to move in a direction transverse to its length.
Rod weeders are known and are conventional agricultural implements. These generally comprise a tool bar mounted upon ground wheels and attached to a hitch for movement of the tool bar across the ground. The rods are then attached to the tool bar on shanks which extend downwardly from the tool bar with the rods parallel to the tool bar and mounted on bearings at the lower end of the shanks. A number of separate rods can be arranged across the tool bar to match the full length of the tool bar. The rod or each of the rods is then driven by suitable mechanism so that it rotates about a longitudinal axis in a reverse direction relative to a normal rolling direction. Such a device is intended to work just below the soil surface to cut weeds and to lift the weed parts to the surface of the soil where they wither and die.
Rod weeders of this conventional type have been well known for many years and have been manufactured and sold in large numbers. However they have a number of significant disadvantages, the most important of these being that as the level of the ground varies relative to the tool bar due to any local changes in surface height, the depth of the rod relative to the surface of the ground significantly varies and unless the rod is working at exactly the right depth, its effectiveness is seriously reduced.
U.S. Pat. No. 3,552,496 discloses an alternative method of mounting the rods on the tool bar by way of a number of flexible shanks which extend downwardly from the tool bar and carry the rods. This arrangement therefore allows some degree of flexing of the rods relative to the ground. The rod is driven by a spitted ground engaging wheel rearward of the rod.
Generally, therefore, it is well known that the rod weeder arrangement is an effective tillage tool. However the constructions available to date have not made the best advantage of the rod weeder technique and is one of the objects of the present invention to provide an improved device for operating the rod weeder technique.